Oxidation of octadecapentaenoic (18:5n-3) acid with soybean 15-lypoxygenase

It is shown for the first time that (3Z,6Z,9Z,12Z,15Z)-octadecapentaenoic acid (ODPA) is readily oxidized with soybean 15-lypoxygenase to form new oxylipins. Based on NMR, UV, and mass-spectrometry, the primary peroxidation product was identified as (13S,3Z,6Z,9Z,11E,15Z)-13-hydroperoxyoctadecapentaenoic acid, and two secondary products were identified as (13S,3Z,6Z,9Z,11E,15Z)-13-hyroxyoctadecapentaenoic and (3Z,6Z,9Z,11E)-13-oxotridecatetraenoic acids. The lipoxygenase oxidation products were found to contain no 9-regioisomers and ketodienes. 6 refs., 1 fig.